Lemon Blueberry Jam Recipe w/o added Pectin
Yield - four 1/2-pint jars
or Juice of 1 lemon
finely grated lemon rind
In large stainless steel or enamel pot, blend with a stick blender or crush with potato masher 3 cups of the blueberries. Add remaining berries, sugar, lemon juice and grated lemon rind.
Bring to a boil over medium-high heat and boil for 20 to 25 minutes or until thick, stirring often. When the jam is as thick as you like, remove from heat, skim off any foam & stir in vanilla extract.
Ladle hot jam into hot jars to within 1/4" of top rim, wipe the rim clean & attach lids.
To preserve jam use preferred safe preservation method.
(I used hot water bath at 5 minutes)